Docker creates .dockerenv and .dockerinit (removed in v1.11) files at the top of the container’s directory tree so you might want to check if those exist. Something like this should work. #!/bin/bash if [ -f /.dockerenv ]; then echo “I’m inside matrix ;(“; else echo “I’m living in real world!”; fi
As stated in the official fish tutorial, you can modify the $fish_user_paths universal variable. Run the following once from the command-line: set -U fish_user_paths /usr/local/bin $fish_user_paths This will prepend /usr/local/bin permanently to your path, and will affect the current session and all future instances too because the -U argument will make the variable universal. From … Read more
This still uses a temp file, but at least it is on one line: echo “text” | cat – yourfile > /tmp/out && mv /tmp/out yourfile Credit: BASH: Prepend A Text / Lines To a File
I was not aware of the award until today when some rookie tried to pin the UUOC on me for one of my answers. It was a cat file.txt | grep foo | cut … | cut …. I gave him a piece of my mind, and only after doing so visited the link he … Read more
Don’t use sed, use cut: grep …. | cut -c 1-N If you MUST use sed: grep … | sed -e ‘s/^\(.\{12\}\).*/\1/’
It basically takes any command line arguments passed to entrypoint.sh and execs them as a command. The intention is basically “Do everything in this .sh script, then in the same shell run the command the user passes in on the command line”. See: What are the special dollar sign shell variables? Need explanations for Linux … Read more
You want: grep -A 5 ’19:55′ file From man grep: Context Line Control -A NUM, –after-context=NUM Print NUM lines of trailing context after matching lines. Places a line containing a gup separator (described under –group-separator) between contiguous groups of matches. With the -o or –only-matching option, this has no effect and a warning is given. … Read more
\b in regular expressions match word boundaries (i.e. the location between the first word character and non-word character): $ echo “bar embarassment” | sed “s/\bbar\b/no bar/g” no bar embarassment
Try this to reload your current shell: source ~/.profile
The UNIX Bash Scripting blog suggests: awk ‘!x[$0]++’ This command is telling awk which lines to print. The variable $0 holds the entire contents of a line and square brackets are array access. So, for each line of the file, the node of the array x is incremented and the line printed if the content … Read more